Adjustable electrified insect screen



Nov. 27, 1934. w. F. FOLMER ADJUSTABLE ELECTRIFIED INSECT SCREEN s She ets-Sheet 1 Filed Oct. 26, 1933 IN VENTOR Z. 70Z7ner Nov. 27, 1934. w. F. FOLMER 1,931,951

ADJUSTABLE ELECTRIFIED INSECT SCREEN Filed Oct. 26, 1933 3 Sheets-Sheet 2 {423A TBORNEY NOV. 27, 1934. '-w FQLMER 1,981,951

ADJUSTABLE ELECTRIFIED INSECT SCREEN 7 2413A]? NEY Patented Nov. 27, 1934 UNITED STATES PATENT OFFICE Folmer-Electracide Corporation, N. Y., a corporation of New York Application October 26,

7 Claims.

My prevent invention relates to insect exterminators and more particularly to high tension electrically charged screens whereby openings, such as doors and windows, are not only provided with a barrier against the entrance of files and similar pests but the insects are destroyed upon making contact with such barrier. application of myself and Harrison L. Chapin, Serial No. 670,140, filed May 9, 1938, there is disclosed and claimed a similar exterminator described as particularly applicable for use in the windows and doors of barns and stables, whereby they may be so screened without greatly interfering with visibility and free ventilation. The present invention is, ingen'eral, an improvement thereon and the improvements are directed in part toward rendering such an exterminating screen or barrier adjustable to fit openings of different widths or lengths and accompanying details of construction whereby the circuit connections are established in a manner not disturbed by the adjusting means. To these and other ends, the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel'features being pointed out in the claims at the end of this specification. In the drawings:

Fig. 1 is a front or outer elevation of an exterminating screen constructed in accordance with and illustrating one embodiment of my invention;

Fig. 2 is a top view thereof;

Fig. 3 is an enlarged horizontal section taken through fragments of one of the positive and negative couples or grids on the line 33 of Fig. 1; Fig. 4 is a similar section, showing a modified construction Fig. 5 is a fragmentary enlarged detail section through both pairs of positive and negative grid couples taken substantially on the line 55 of Fig. '7, showing the circuit connection between the negative grids;

Fig. 6 is an elevation of the inside of the exterminating screen, partly broken away to show the circuit connections between the positive grids;

Fig. 7 is a fragmentary enlarged duplication of the upper left hand corner thereof, broken away and more in detail, but showing the same modification of the electrodes as in Fig. 4;

Fig. 8 is an enlarged vertical sectional view through one of the grid couples taken substantially on the line 8-6 of Fig. 1;

In the prior pending Rochester,

1933, Serial No. 695,351-

Fig. 9 is a similar section through the entire screen taken on the line 99 of Fig. 1;

Fig. 10 is a similar section through the entire screen taken on the line 10-10 of Fig. 1, and

Fig. 11 is a section through the entire screen taken on the line 1111 of Fig. '7.

Similar reference numerals throughout the several views indicate the same parts.

Referring more particularly to the drawings and first to Figs. 1 and 6 thereof, and also Fig. 2, the major elements of the screen consist of two inner and outer frames 1 and 2 slidable upon each other to be extended or contracted and thereby be fitted in and supported by win dow or other openings of different widths in a well known manner. 'To this end, the proximate faces of the top and bottom horizontal rail cf each frame are provided with T-shaped slots or runways in which correspondingly formed metal guide blocks 3 (see the sectional views) are fitted. These are secured at intervals to one or the other of the frames by screws 4 so that the frames are locked together in definitesliding contact. Stop cleats 5 are secured on opposite sides of opposite ends of the frames, as clearly appears in Figs. 1

and 2. 'As the two frames are substantially identical, a description of one will suffice for both. I

Taking inside screen 1, which is chosen because it carries the terminal connections and because it appears alone in the section of Fig. 8, there is secured to the inner side thereof by screws 6 a grid plate 7 having two series of closely associated elongated openings 8 stamped therein in such 'manner that the intervening metal takes the form of spaced wires 9 and these, we will say, constitute the negative electrodes of the couple. In

effect, therefore, except for the fact that I prefer a one-piece stamping, the plate 7 constitutes a frame with spaced wires in its center. This plate 7 is 'preferablyoifset from frame 1, as shown in Fig. 8, and supported by and parallel to itwithin the opening of frame 1 is another similarly formedplate 10 providing spaced positive electrodes or wires 11. The supporting means consists of four insulating brackets, one near each corner, that hold the two plates or grids properly "spaced according to the potential of the current used. The electrodes or wires 9 and 11 on the two, respectively, are alternated, that is, one is opposite the opening 8 of the other, as clearly appears in Figs. 1 and 3, and the idea is, of course,

that while fresh air can pass freely through the screens or grids insects seeking to pass will contact at some point with positive and negative elecpreviously referred to, of a heavy plate 12 of suit- 7 able insulating material, such as compressed mica composition having one end fastened to the inner positive grid plate by bolts 13' and the other end fastened to the outer negative grid plate by bolts 14. With respect to one of the brackets onnegative grid couple on each frame, and brushes this particular inner frame 1, which we are describing, one of the bolts 13 and 14- in each case is secured with a binding post 15 instead of a nut or nut plate 16 projecting from the inner side and having the usual opening and threadedhead 17 for the attachment of the positive and negative supply wires. Each gridframeor plate is provided with an opening 18 opposite the bracket fastening devices or bolts of the other, those on the posterior being indicated by that reference numeral and those on theinterior being indicated at 19 to provide a safe gap against arcing and avoid any electrical contacts.

, It is also desirable to protect these bracket connections and the openings just described from the "weather where they would otherwise be exposed on the outer side of the'screen as a whole. To this end, rain sheds or shields 20 are provided to cover the openings 19 on the forward side of positive grid 10 and to cover the openings 18 on the outdoor side of negative grid 7-.carried by .frame 2. These consist, in the present instance, of cup shaped stampings fastened to the grids by the bolts 13 or 14 and by-additional screws 21. I have already referred to the fact that the feed wires, shown at A and B in Fig. 6, go to the binding posts 17, respectively mounted upon and electrically connected to the positive and negative grids of the inner frame 1. Means must be provided for communicating corresponding polar- -ities tothe grids of the outer frame 2. This is accomplished in the following manner: e The inner positive grids 11 are flanged at top and bottom, as indicated at 22, and also have at least one end flange 23 to add to their rigidity, 1 inasmuch as they are not fastened at their edges as are the outer grid plates and on one of these end flanges I fasten at 24 a metallic spring finger or brush 25, as clearly shown in Figs. 6 and 9.

This brush electrically contacts and slides upon the upper flange 22 of theother inner grid so that in any position of adjustment both of these grids are positively charged from wire A. Similarly, a like brush 26 securedat 27 to one of the outer grid plates '7, as shown in Fig. 5 and in dotted lines in Fig. 6, reaches across above the I positive grids 10 andslides upon the outer grid plates 7 of the opposite frame so that these are both negatively connected.

Referring to the modification illustrated in Figs. 4 and '7, the principle involvedis the same but instead of having the electrodes or wires 9 in two lines in the parallel planes of the respective positive and negative grids or platesI offset them both inwardly as shown, so that they all liein one plane, as indicatedat 9. 5

A screen or electrified barrier constructed in accordance with my invention has all the advantages, as to fitting, of the ordinary adjustable wire mesh fly screen but destroys the insects instead of merely excluding them and at the same time affords better ventilation.

I claim as my invention:

1. In an electrified insect exterminator, the combination with a pair of relatively adjustable frames, of a positive and negative grid couple on each frame, and means electrically connecting units of the couples of like polarity.

2. In an electrified insect exterminator, the combination with a pair of frames slidably adjustable one upon the other, of a positive and electrically connecting the grid units of like polarity embodying a brush carried by one and having wiping contact with the other. 3. In an electrified insect exterminator, the

combination with a pair of frames "slidably adjustable one upon theothenof grids'of a'like polarity on the respective framesyan intervening grid of opposite polarity, and a brush on one of the first mentioned grids engaging the other to connect them in circuit. I

4. In an electrified insect exterminator, the combination with a pair of frames slidably adjustable one upon the other, of a positive and.

p'roximateones being of the same polarity and.

the outer ones being of opposite polarity and being provided with insulated brackets by means of which the inner ones are supported, and brushes electrically connecting the units of the couplesthat are of like polarity.

6. In an electrified insect exterminator, the combination with a frame, of a grid-of one polarity secured thereto and divided into a plurality'of electrodes, a second grid of opposite polaritysimilarly divided into a plurality of. electrodes ar-,.,

ranged parallel to those first mentioned, and insulated brackets having fastening devices by means of which the grids are spaced and the last mentioned is supported .by the first mentioned,

each grid being provided with cut-away portions opposite the fastening devices on the other grid.

.7. In an electrified insect exterminaton the combination with a frame, of a grid of one polarity secured thereto and divided into a plurality of electrodes, a second grid-of opposite polarity similarly divided into a plurality of electrodes ar--" ranged parallel to those first mentioned, insulated brackets having fastening devices by means of which the grids are spaced and the last mentioned is supported by the first mentioned, each grid being provided with cut-away portions oppo-'- 

